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`case' expression with list literal behaves differently in pcDefinePCell than in the toplevel

tweeksii 
;; The `case' expression in this pcell is expected to return "V2", but it
;; returns `nil' instead. Why?
(pcDefinePCell (list (ddGetObj "dungeon") "case_in_pcell" "layout")
    ((metal1_layer "M2")
     (metal2_layer "M3"))
  (let (via_layer)
    (fprintf stdout "%A\n" (list metal1_layer metal2_layer))
    (case (list metal1_layer metal2_layer)
      ((("M1" "M2")) "V1")
      ((("M2" "M3")) "V2"))
    (fprintf stdout "%A\n" via_layer)
    (rodCreateRect ?layer via_layer)))

> (load "~/skill/case_in_pcell.il")
Generating Pcell for 'case_in_pcell layout'.
("M2" "M3")
nil
*WARNING* (ROD-1011) rodCreateRect: required argument "?layer" not specified or nil
*WARNING* (ROD-1075) rodCreateRect: command failed in "dungeon/case_in_pcell/layout"
t
> getVersion
"@(#)$CDS: virtuoso version ICADV12.3-64b 09/01/2017 10:34 (sjfhw305) $"
> getVersion t
"sub-version ICADV12.3-64b.500.14 "
> metal1_layer = "M2"
"M2"
> metal2_layer = "M3"
"M3"
> (case (list metal1_layer metal2_layer)
((("M1" "M2")) "V1")
((("M2" "M3")) "V2"))
"V2"

Am I going insane?  ⊙﹏⊙

  • Hi Tom,

    I don't see the variable via_layer being assigned, but also I am a little confused by the format of your case statement, partly because I know that 'case' allows for alternative matches in the first item which are represented as a list of choices, but it looks as though you may have dealt with that already?  Anyhow, perhaps try the following:

    
(pcDefinePCell (list (ddGetObj "dungeon") "case_in_pcell" "layout")
    ((metal1_layer "M2")
     (metal2_layer "M3"))
  (let (via_layer)
    (fprintf stdout "%A\n" (list metal1_layer metal2_layer))
    (setq via_layer (case (list metal1_layer metal2_layer)
      ((("M1" "M2")) "V1")
      ((("M2" "M3")) "V2")))
    (fprintf stdout "%A\n" via_layer)
    (rodCreateRect ?layer via_layer)))

    Hopefully it was just the varibale assignment that you overlooked?

    Cheers,

    Lawrence.

  • in reply to skillUser

    Hi Lawrence,

    Thank you for fixing my bug!  You're right, adding the setq fixed it.  ^_^;

    Somehow this equivalent code (with the setq) does not work inside my org's custom pcell compiler, however.... Disappointed  But I'm on my own for that one.

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